I. Field
The following description relates generally to wireless communications and more particularly to updating access node neighbor lists in a wireless communications network.
II. Background
Wireless communication systems are widely deployed to provide various types of communication and to communicate information regardless of where a user is located (e.g., inside or outside a structure) and whether a user is stationary or moving (e.g., in a vehicle, walking). For example, voice, data, video and so forth can be provided through wireless communication systems. A typical wireless communication system, or network, can by multiple-access systems capable of supporting communication with multiple users by sharing the available system resources (e.g., bandwidth and transmit power). A system can use a variety of multiple access techniques such as Frequency Division Multiplexing (FDM), Time Division Multiplexing (TDM), Code Division Multiplexing (CDM), Orthogonal Frequency Division Multiplexing (OFDM), 3GPP Long Term Evolution (LTE), and others.
Generally, a wireless multiple-access communication system can simultaneously support communication for multiple wireless terminals. Each terminal communicates with one or more base stations through transmissions on the forward and reverse links. The forward link (or downlink) refers to the communication link from the base stations to the terminals, and the reverse link (or uplink) refers to the communication link from the terminals to the base stations. This communication link can be established through a single-in-single-out, multiple-in-single-out or a multiple-in-multiple-out (MIMO) system.
A MIMO system employs multiple (NT) transmit antennas and multiple (NR) receive antennas for data transmission. A MIMO channel formed by the NT transmit and NR receive antennas can be decomposed into NS independent channels, which are also referred to as spatial channels, where NS≦min{NT, NR}. Each of the NS independent channels corresponds to a dimension. The MIMO system can provide improved performance (e.g., higher throughput and/or greater reliability) through utilization of the additional dimensionalities created by the multiple transmit and receive antennas.
A MIMO system supports time division duplex (TDD) and frequency division duplex (FDD) systems. In a TDD system, the forward and reverse link transmissions are on the same frequency region so that the reciprocity principle allows the estimation of the forward link channel from the reverse link channel. This enables the access point to extract transmit beamforming gain on the forward link when multiple antennas are available at the access point.
Communication systems can include a multitude of access nodes through which end nodes (e.g., mobile devices) are coupled to a network. End nodes typically communicate with access nodes (e.g., access router) directly through established connections. Such communication systems rely on a bidirectional communications link between the end node and the access node to support two-way communication between the nodes. Access nodes that are serving neighboring geographic cells might be known to each other through manual configuration during which various parameters are configured in an access node corresponding to several of its neighbors. Such configuration can be labor intensive and error prone due to human error and the fact that the network layout of a wireless network can change due to network expansion, gradual phased deployment of a system, environmental conditions, as well as other factors.